<template>
  <view>
    <my-search @click="gotoSearch"></my-search>
   <view class="scroll-view-container" >
     <!-- 左侧滑动区域 -->
     <scroll-view scroll-y="true" :style="{height:wh+'px'}" class="left">
       <block v-for="(item,i) in cateList" :key='i'>
          <view :class="['left-scroll-view-item',i === active?'active':'']" @click="activeChanged(i)">{{item.cat_name}}</view>
       </block>
     </scroll-view>
     <!-- 右侧滑动区域 -->
     <scroll-view scroll-y="true" :style="{height:wh+'px'}" :scroll-top="scrollTop">
        <view v-for="(item2,i2) in cateLevel2" :key="i2" class="cate-lv2">
          <view class="cate-lv2-title"> / {{item2.cat_name}} /</view>
          <!-- 动态渲染三级分类的列表数据 -->
              <view class="cate-lv3-list">
                <!-- 三级分类 Item 项 -->
                <view class="cate-lv3-item" v-for="(item3, i3) in item2.children" :key="i3" @click="gotoGoodsList(item3)">
                  <!-- 图片 -->
                  <image :src="item3.cat_icon.replace('dev','web')"></image>
                  <!-- 文本 -->
                  <text>{{item3.cat_name}}</text>
                </view>
              </view>
        </view>
     </scroll-view>
   </view>
  </view>
</template>

<script>
   import badgeMix from "@/mixins/tabbar-badge.js"
  export default {
     mixins:[badgeMix],
    data() {
      return {
        wh:0,
        active:0,
        scrollTop:0,
        cateList:[],
        // 二级分类列表
        cateLevel2:[]
      };
    },
    onLoad() {
      const sysInfo = uni.getSystemInfoSync()
      // console.log(sysInfo);
      this.wh = sysInfo.windowHeight-50
      this.getCateList()
    },
    methods:{
      async getCateList(){
        const {data:res} =  await uni.$http.get('/api/public/v1/categories')
         // 判断是否获取失败
            if (res.meta.status !== 200) return uni.$showMsg()
            // 转存数据
            this.cateList = res.message
            this.cateLevel2=res.message[0].children
      },
       // 选中项改变的事件处理函数
        activeChanged(i) {
          this.active = i
          this.cateLevel2=this.cateList[i].children
          this.scrollTop = this.scrollTop === 0 ?1 :0
        },
        // 跳转到商品列表页面
        gotoGoodsList(item){
          uni.navigateTo({
            url:'/subpkg/goods_list/goods_list?cid='+item.cat_id
          })
        },
        gotoSearch(){
          uni.navigateTo({
            url:'/subpkg/search/search'
          })
        }
    }
  }
</script>

<style lang="scss">
 .scroll-view-container{
   display: flex;
   .left{
     width: 120px;
   }
   .left-scroll-view-item{
     background-color: #f7f7f7;
     line-height: 60px;
     text-align: center;
     font-size: 12px;
     &.active{
       background-color: #fff;
       position: relative;
       &::before{
         content: '';
         display: block;
         width: 3px;
         height: 30px;
          background-color: red;
          position: absolute;
          top: 50%;
          left: 0;
          transform: translateY(-50%);
       }
     }
   }
   .cate-lv2-title {
  font-size: 12px;
  font-weight: bold;
  text-align: center;
  padding: 15px 0;
}
.cate-lv3-list {
  display: flex;
  flex-wrap: wrap;

  .cate-lv3-item {
    width: 33.33%;
    margin-bottom: 10px;
    display: flex;
    flex-direction: column;
    align-items: center;

    image {
      width: 60px;
      height: 60px;
    }

    text {
      font-size: 12px;
    }
  }
}
 }
</style>
